This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This pilot clinical study is to determine if 5% imiquimod cream (Aldara, 3M Pharmaceuticals), an FDA-approved drug for use in other skin cancers, can be used to induce an immune response in patients with primary melanoma skin cancers. Eligible subjects will be referred from the Harbor-UCLA Dermatology Clinic or Surgical Oncology service for study evaluation. Patients will be under the care of Dr. Hernan Vargas, associate professor of Surgical Oncology and will receive the current standard of care for primary melanoma skin cancer-surgical removal. This study will add an additional intervention to the current standard of care. Patients will have a 50-50 chance of receiving placebo or medication. Patients will apply the study medication, a topical cream, to the site of the melanoma skin cancer for 2 weeks during the time they would normally wait for their scheduled surgery. Patients will come for an initial visit to the General Clinical Research Center at Harbor-UCLA. Here they will meet with the research fellow to obtain full disclosure of the study risks and benefits and consent to inclusion in the study. Inclusion or exclusion from the study will in no way affect whether they receive the standard of care. After informed consent, an initial examination will be completed, the patient's skin cancer will be photographed and an initial 100cc (approximately 7 tablespoons) of blood will be collected. Patients will be given the study medication by the investigational pharmacy.